Has the AI (esp in the Campaign) got dumber since 4.0?

I'm playing through the campaign again now that I have TrackIR support, and I'm noticing that the enemy AI are just getting up to my ship and then going VERY, VERY slowly in circles around my ship; to the point where I'm almost stationary if I want to get them in sights and shoot them.

This is VERY different to my first two times through the campaign. 

Has this just changed?

I'd like to know if I need to raise a bug for it or if it's under investigation already.